Pressure sensors are utilized in a wide variety of environments. One particular use of a pressure sensor is in combination with a velocity sensor in water treatment systems where water flow measurement is typically required for municipalities, including measuring run-off water, water in storm drains or sewers, water running in rivers, lakes, et cetera. However, the amount of flow in any of these systems can be unpredictable and vary with time. Because normal wastewater flows may increase due to storms or other unexpected or uncontrolled events, sewer pipes or sewer systems typically are constructed to be large enough to handle most excessive flow events. Consequently, absent an unexpectedly high fluid collection, wastewater conduits are partially filled and act as open channels. The flow depth typically is only a fraction of the conduit depth. Measuring the flow rate of a fluid in an open conduit poses some challenges.